Monday, June 11, 2007

1500 Year Periodic Warming Measured During the Last 4000 Years. Man Caused?

I just came across this article in "Geology" magazine, "peer reviewed I presume. It is more than interesting that this 1500 year periodicity of climate change, (warming and cooling) agrees with the same general time frame associated with climate changes measured in deep-sea sediment cores taken from the North Atlantic Ocean. A mere coincidence? Hardly. The fact that these warming and cooling events occured in the absence of man, "suggests" strongly that carbon dioxide in the atmosphere is NOT a cause, or a "driver" or a "forcing mechanism", or involved in any other way.

But now there are those trying to get us to believe that man's input of carbon dioxide into the atmosphere is causing global warming. Would that concept stand up in a court of law? Would a "reasonable man" conclude that man is causing global warming? Come on all you lawyers out there, give me a hand.Peter

Fourier and nonlinear regression analysis of a 4000+ yr paleoclimate proxy record in western Canada shows strong periodicities of approximately 1500 yr and several weaker century- to millenial-scale periodicities. In conjunction with the 23708 yr Milankovitch periodicity, these produce a model of climate fluctuation through the postglacial consistent with recognized paleoclimatic fluctuations of the past 15000 yr in the northern mid-latitudes. These results suggest that postglacial climatic anomalies such as the Little Ice Age and the Younger Dryas were at least in part periodic phenomena rather than the result of unique, aperiodic events. Projecting these periodicities into the future suggests that even in the absence of anthropogenic climate forcing, a natural warming trend will continue until ca. A.D. 2400.This record provided courtesy of AGI/GeoRef.